<?php
$s="123abc汉";
echo $s,"\n";
echo $s[0],$s[3],$s[6],"\n";
echo 'I\'m a student',"\n";
echo "He say:\"I'm a student\"\n";
$a=123;
$b=6789;
echo "$a+$b=",$a+$b,"\n";
$go='去';
$goo="咕咕叫的声音";
$goo="好的";
$goo="商品";
echo "{good}s是什么意思？{$goo}ds\n";
$a=['2401','name'=>'张三','age'=>18];
echo "学号：$a[0],姓名：$a[name],年龄：$a[age]\n";
echo "学号：{$a[0]},姓名：{$a['name']},年龄：{$a['age']}\n";
$a=[['2410','name'=>'zs'],['age'=>18]];
echo "学号：{$a[0][0]},姓名：{$a[0]['name']},年龄：{$a[1]['age']}\n";